Until Reforged, the forward slash '/' is an illegal path for Warcraft III and you should NOT USE IT. Instead, you should use the backwards slash '\' which is the way to separate folders on Warcraft III and Windows. This has been the case for 20 years. Reforged tries to support the forward slash '/', but it can probably still cause issues. In general, you should just never use the forward slash '/' on Warcraft III modding unless you can't help it (such as due to a Reforged thing).